I worked for a short time in a Public Defender's office. Here's my impressions based on that experience:
1. Attorneys are required (usually by law and/or the ethics of their profession) to represent their clients (even scumbags) to the best of their abilities. A few years ago, the phrase "required to
zealously represent their clients" was changed to something not quite as strong (but I forget the exact words).
2. Defense attorneys get paid to do a job. They don't get paid much, but they do get paid. If the job says they gotta do it, they gotta do it.
3. Attorneys are not required to lie for their clients. This means that if a client tells his lawyer that he's guilty, but insists on pleading innocent, the lawyer can ask the judge to excuse him (the attorney) from the case. I'm not sure how often this sort of thing actually happens.
4. Our justice system is adversarial in nature. That means that the prosecutors push for as much as they can, and the defense pushes back as hard as they can. Then it's up to the judge and jury to decide how justice and the law apply. I've seen prosecutors go overboard in their efforts, IMHO. I guess that's their job. Just as the defense tries to protect their clients. Even if it means getting a client off on a mere technicality.
5. I think that in order to work in the criminal legal system, the attorneys have to really really believe that the system works well. They have to believe that if both the prosecution and the defense do their jobs right, that real justice will be served. Remember, defense attorneys aren't there to be the judge and jury. They're there to present ONE and only ONE side of the case.
6. In direct contradiction to #5 (above), I think that some defense attorneys (purposefully) just don't think about it. It's kind of like a psychological defense mechanism.
7. I talked with the attorney who defended John Wayne Gacy (mass murderer who buried boys in his house, crawlspace, backyard, etc. - was finally executed a few years back). He was absolutely convinced that Gacy was not working alone (Gacy was the only one ever convicted in these murders). I think it's possible that this could be true. But it's also possible that the attorney simply
created an explanation that his mind could accept, which would justify his representing Gacy. I dunno.
8. In reference to the scumbag who videotaped murdering his girlfriend: His attorney probably justified the "not guilty" plea because technically, it's not murder if his client is insane, or didn't premeditate it, or something like that. Or, this particular lawyer could belong to #9 (below).
9. Some attorneys are scumbags. Remember, a lot of them enter politics, like Bill and Hillary.
That being said, I ain't ever gonna work for PD again. The attorneys there were great, but I really really hate scumbags.